Nanodrugs therapy for combating antimicrobial resistance: a review on green silver nanoparticles

Background: A nanotechnology-based approach offers researchers an opportunity to address the challenges of antimicrobial resistance. In this review, we summarize the antimicrobial properties, mechanisms, current synthesis trends, and limitations of green silver nanoparticles. Methods: The review examines a wide range of scientific databases, such as ScienceDirect, Scopus, PubMed, Google Scholar, and Web of Science, to assess the effectiveness, mechanisms of action, and synthesis of silver nanoparticles in overcoming the challenges of antimicrobial resistance. It accentuates the complexity concerns of using crude extracts and compound isolates in the synthesis of silver nanoparticles. Results: The use of crude extracts as reducing, capping, and stabilizing agents has been widely explored in the synthesis of silver nanoparticles because it is eco-friendly, non-hazardous, and economical. However, diversity and complexity present in the composition of crude extracts, with resultant effects on the size, shape, crystal structure, purity, reproducibility, surface chemistry, and toxicity of the silver nanoparticles, are a common challenge. The use of pure compound isolates has been suggested for the synthesis of silver nanoparticles to develop novel antimicrobial drugs for combating multidrug resistance. Conclusion: The use of pure compound isolates for synthesizing silver nanoparticles offers better control compared to crude extracts. However, it is crucial to consider factors such as the cost of isolation and purification, limited availability, reduced synergistic effects, and toxicity concerns at high concentrations of pure compounds, which potentially restrict their use as antimicrobial drugs.